Attachment for lathes



Feb. 13, 1940. W, A, STONE 2,189,968

' ATTACHMENT FOR LATHEs Filed July e. 193s l T... H

1N V ENTOR.

I/I/ALTE/f?ASTO/VEY 1 BY l ATTORNEY.

' V the feed tube of a lathe at any desired pointk Patented Feb. 13,A194() `This invention relates yto attachments"- for lathes and'i moreparticularly to a'device adapted to-.be positioned in the ieed tube of alathe'fto acti as la stop, whereby in the case of a member i requiringa, machined operation at each end `thereof the member may bemerelyreversed andy thevposition of the stop determine the properposition oi the member.' 4

A primary object of this invention is the provision of such a stop whichmay bepositioned in therein and held. in its desired' position without.thenecessityof' the useof set screws or analogous devices. e a f' e Asconductive to a clearer understanding .of this invention. it mayy herebe pointed out `that in certain types of work requiring thev use of amachine or hand lathe or a screwginachineor e analogous device the workbeing operated upon `may reduire identical or similar machine operationsat opposite ends thereof.

i of the work, he may simply reverse the sameand insert the machined endthereof into the feed tube, which end, when itfabuts the stop, indicatesthat the work is in proper measured posia s rigid relationship with thestopmand hence the fee'dtubei` v tion for machining of the other end.Heretofore such stops have been held in place` by various mechanismswhich required disarrangement of the machine, as, in the case ofset`screws=hav" ing their heads positioned exteriorly .ofthe feed tube,in which case it has hithereto been necessary to tap the feed tube andthread the holes so tapped.

It is an object of this invention, therefore, toly i provide a stopwhich may be inserted in a feed tube and secured in position thereinwithout the necessity of tapping the tube or resorting to anydisarrangement of the mechanism ofv whatsoever.

Other objects will in part he obvious and in part pointed outhereinafter.

the lathe The invention accordingly consists inthe combinations ofelements, arrangements of parts andl features of construction all aswill be moreV fully pointed out and shown in the accompanying drawingwherein Figure 1 is a side elevational View of a conventional lathe, a ve i e Figure 2 is an enlarged sectional View taken substantially alongthe line 2--2 of `Figure 1,

Figure 3 is an enlarged detail view showing the 1 s In such cases it iscustomary to, position a stop in the feed tube of the lathe or othermachine at a denite meas-- ured position ltherein whereby, whentheoperator has completed the required machining of oneA end" therewith.

vention,uand

at lli, of any desired type 'including ahead lit' V yFigure 4` is asectional view taken along the line'l E14-i1 of Figure 3'as-viewed` fromthe leftil i e e provided with a live center ,l2 and a work holder` v yor tool. carriage i3 provided with` adeadcenter.

(not shown).A Power maybe supplied tothe motor M connected by means of adrive wheel j l5 and belt [i6 to"a` drive pulley Il connected "to sadrive shaft I8. The "interior of head llfniay 'be of anyconventional-fconstruction but ispro vided with a centrally located`feed tube 20 and suitable pulleysrZI connected inV any desired vman``lathe in any' suitable manner as by meansloiA a f 1C ner tddriVe-shafti8 to permit rotation'bf the work. i

The deviceof the instantinvention comprises a st op` 25"provided atr itsextremity with a suitably designed yaperture -2ty tok 'accommodate thevend'of any-desired piece of work as lindicated in Suitable locking jaws`(not e dotted lines at 2l.

shown) or a 'locking key `28(s1ee Figure 3) are.-`

provided in order. thatthe workmay be heldin Havingreference now` to 3the endofw stop .25 opposite aperture 26y is lprovided with a" cuporrecess 350 surrounded bytongues 3l ta* pered bothxinternallygandexternally as indicatedl at 32 and '33. Extending.; inwardly from thelbottom of recess 3 is 4a threaded aperture 35. 1 I Locking of the stopinthe feed tubeis eiected by expansion of tongues 3| and their tightfrictional engagement with the sidesof the feed tubein 'a manner now tobe described.

A key or expander generally indicated atlll` i 'is adapted to be fittedinto recess 30'. Expander i0 is comprised of a tapered yendy portion 4lof a diameteradapted to iit closely` `within recess e 3i) and providedat its extremity with a threaded suitable t'ool positioned 'ini `relatedassembly From the foregoing the operation of the device V member i2adapted *to engage vthreaded vrecess I35, anda shaft 43 whichextendsfrom member 4l to the exterior of-the'ife'ed-tube and housing i l insuch manner thatit may be rotated by any should be' readily understood.Stop 25 is fitted into feed tube 20 from the left as viewed in rFigi4locking mechanism ofthe stop ofthe instant ini i I aperture 2S from thetoolholder I3 carefully measured in any desired manner. Expander 4B isthen introduced into recess 3) and. rotated in suclimanner that threadedextremity 42 eny gagesthreaded aperture 35. As such rotation iscontinued tapered member il causes tapered itongueSl toexpand into tightfrictional engagement with the sides of feed tube 2Q which enuntil such.time as reverserotation of shaft 43 causes retraction of tapered member@l to permit gagement holds stop 25 in the desired position resilientcontraction of tongues 3l lwlfiereupori the stop maybe removed orshifted to a new lposition in the feed tube. y

It will now be Iseen that there isfherein provided a stop which may bepositioned inthe feed tube of any lathe or analogousl device and `re''that al1 mattershereinbefore described or shown in the accompanyingdrawing is to be interpreted merely as illustrative and not in alimiting sense.

`I claim as my invention: p

1 A` stop for positioning in the feed tubey of ures l and 2 and thedistance of the base of a Work holding machine comprising a memberprovided at one end with Work engaging means and at its other end with arecessed portion provided witha threaded cup at its inner extremity, aplurality of resilient members forming the sides of said recessedportion', means to expand said members into relatively tight frictionalengagement with the bore ofA said feed tube and retain the same in `saidengagement, said last mentioned means comprising a member `provided witha rthreaded portion engaging said cup, a conical portion serving toexpand said resilient members as said threaded portion is screwed intosaid cup. 2. A stop for positioning in the feed tube of a' workhcldingmachine comprising a member provided kat one end with a work holdingIrecess and at the other end with a plurality of f expansible` .membersadapted to expand into relatively7 tight frictional engagement with thebore of said feed tube and means to expand said members.

' 3.` A stop yfor positioning in the feed tube of work holding machinecomprising a member provided vat one end with a work holding recess andat the other end with a plurality of expansible members adapted toexpand into relatively tight irictional engagement with the bore of saidfeed tube and means to expand said members, said last mentioned meanscomprising a key havmg a conical portion adapted upon insertion betweensaid resilient members to force the same towards said tube. WALTERA.STONE.

